Orthogonal frequency division multiplexing (OFDM) has generated great interest for future high rate wireless communications due to its advantages in mitigating the hostile channel selectivity while enabling a high spectrally efficient modulation technique. Multiple Input Multiple Output (MIMO) technique has emerged as one of the most significant techniques since it could offer substantial improvements over conventional systems in either bit error rate (BER) performance or capacity (transmission data rate) through space diversity or spacing multiplexing. See S. Alamouti, “A simple transmitter diversity scheme for wireless communications,” IEEE J. Select. Areas Commun., vol. 16, pp. 1451-1458, October 1998; V. Tarokh and A. Seshadri, “Space-time codes for high data rate wireless communication: Performance criterion and code construction,” IEEE Trans. Inform. Theory, vol. 44, pp. 744-765, March 1998 and G. J. Foschini and M. J. Gans, “On limits of wireless communications in a fading environment when using multiple antennas,” Wireless Personal Communications, vol. 6, pp. 311-335, March 1998.
The combined MIMO-OFDM approach, therefore, is quite suitable for future wireless broadband networks by taking advantage of both OFDM and MIMO techniques. However, MIMO-OFDM system suffers severe performance degradation due to phase noise which is caused by the random phase fluctuation of oscillators at either the transmitter or the receiver. Even though various methods have been proposed in the literature to mitigate small phase noise, they are specifically designed for single-antenna systems See P. Robertson and S. Kaiser, “Analysis of the effects of phase noise in orthogonal frequency division multiplexing (OFDM) systems,” in Proc. ICC'95, (Seattle, Wash.), pp. 1652-1657, 1995.; and S. Wu and Y. Bar-Ness, “A phase noise suppression algorithm for OFDM based WLANs,” IEEE Commun. Lett., vol. 6, pp. 535-537, December 2002.